/*
*	ID : Pallab
* 	PROG : D
* 	LANG : C++
* 	2012-11-29-19.23.16 Thursday
*
* 	"I have not failed, I have just found 10000 ways that won't work.
*/
#include <iostream>
#include <algorithm>
#include <vector>
#include <sstream>
#include <fstream>
#include <string>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <numeric>
#include <stack>
#include <functional>
#include <bitset>
#include <iomanip>

#include <ctime>
#include <cassert>
#include <cstdio>
#include <cmath>
#include <cstring>
#include <climits>
#include <cstring>
#include <cstdlib>

using namespace std;

#define foR(i1,st,ed) for(int i1 = st , j1 = ed ; i1 < j1 ; ++i1 )
#define fo(i1,ed) foR( i1 , 0 , ed )
#define foE(i1,st,ed) foR( i1, st, ed+1 )
#define foit(i, x) for (typeof((x).begin()) i = (x).begin(); i != (x).end(); i++)
#define bip system("pause")
#define Int long long
#define pb push_back
#define SZ(X) (int)(X).size()
#define LN(X) (int)(X).length()
#define mk make_pair
#define SET( ARRAY , VALUE ) memset( ARRAY , VALUE , sizeof(ARRAY) )
#define line puts("")

inline void wait(double seconds) {
        double endtime = clock() + (seconds * CLOCKS_PER_SEC);
        while (clock() < endtime) {
                ;
        }
}
template<class T>
inline T fastIn() {
    register char c=0;
    register T a=0;
    bool neg=false;
    while(c<33)c=getchar();
    while(c>33) {
        if(c=='-') {
            neg=true;
        } else {
            a= (a*10)+(c-'0');
        }
        c=getchar();
    }
    return neg?-a:a;
}
const int MX = (int)1e5+5;
int node_count,edge_count;
vector<int> adj[MX];
int ai[MX];
inline void read(){
    node_count=fastIn<int>(),edge_count=fastIn<int>();
    fo(i,edge_count){
        int u=fastIn<int>()-1,v=fastIn<int>()-1;
        adj[u].pb(v),adj[v].pb(u);
    }
    fo(i,node_count)ai[i]=fastIn<int>();
}
int cur_ai[MX];
bool marked[MX];
inline void proc(){
    SET(cur_ai,0);
    queue< int >q;
    SET(marked,false);
    fo(i,node_count){
        if(cur_ai[i]==ai[i])q.push(i);
    }

    while( q.empty()==false ){
            int f=q.front();q.pop();
            if(marked[f])continue;
            marked[f]=true;
            ++cur_ai[f];
            for(auto &x:adj[f]){
                ++cur_ai[x];
                if( cur_ai[x]==ai[x] )q.push(x);
            }
    }
    int res=count(marked,marked+node_count,true);
    string ss="";cout<<res<<'\n';
    fo(i,node_count)if(marked[i])cout<<ss<<i+1,ss=" ";
    line;
}
int main() {
        int kase = 1;
#if defined( xerxes_pc )
        if (!freopen("in1", "r", stdin))
                puts("error opening file in "), assert(0);
        kase = 1;
#endif
        fo(i,kase){
                read();
                proc();
        }
        return 0;
}
